USGS Volcano Hazards Program Volcano Update


AVO update page and observatory web site


Elevated surface temperatures and a lava dome in the summit crater were detected in satellite images this week. Analysis of satellite data obtained on January 30 shows a lava dome, about 100 m (330 ft.) in diameter, within the 200 m (650 ft.) diameter summit crater. Persistent elevated surface temperatures since about January 24 and satellite observations of a lava dome warranted the change in aviation color code and volcano alert level to ORANGE/WATCH on February 6. A clear satellite view of the summit crater on February 2 showed no change in the size and shape of the lava dome. Since then the summit has been obscured by clouds and AVO has received no additional information about unrest at the volcano.

The development of a lava dome in the summit crater indicates that sudden explosions of blocks and ash are possible with little or no warning. Ash clouds, if produced, could exceed 20,000 feet above sea level. If a large ash-producing event occurs, nearby seismic, infrasound, or volcanic lightning networks should alert AVO staff quickly. However, for some events, a delay of several hours is possible. There is no real-time seismic monitoring network on Mount Cleveland and AVO is unable to track activity in real time.Cleveland volcano forms the western half of Chuginadak Island, a remote and uninhabited island in the east central Aleutians. It is located about 75 km (45 mi.) west of the community of Nikolski, and 1500 km (940 mi.) southwest of Anchorage. The volcano's most recent significant eruption began in February, 2001 and it produced 3 explosive events that produced ash clouds as high as 12 km (39,000 ft) above sea level. The 2001 eruption also produced a rubbly lava flow and hot avalanche that reached the sea. The most recent minor ash emissions were observed in November 2012.

Update in Common Alerting Protocol (CAP) format